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  <title>取得一个脚本中所有日期时间函数所使用的默认时区</title>
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  <div id="layout-content"><div id="function.date-default-timezone-get" class="refentry">
 <div class="refnamediv">
  <h1 class="refname">date_default_timezone_get</h1>
  <p class="verinfo">(PHP 5 &gt;= 5.1.0, PHP 7)</p><p class="refpurpose"><span class="refname">date_default_timezone_get</span> &mdash; <span class="dc-title">取得一个脚本中所有日期时间函数所使用的默认时区</span></p>

 </div>
 <div class="refsect1 description" id="refsect1-function.date-default-timezone-get-description">
  <h3 class="title">说明</h3>
  <div class="methodsynopsis dc-description">
   <span class="methodname"><strong>date_default_timezone_get</strong></span>
    ( <span class="methodparam">void</span>
   ) : <span class="type">string</span></div>

  <p class="para rdfs-comment">
   本函数返回默认时区，使用如下“假定”的顺序：
   <ul class="itemizedlist">
    <li class="listitem">
     <p class="para">
      用 <span class="function"><a href="date_default_timezone_set.html" class="function">date_default_timezone_set()</a></span>
      函数设定的时区（如果设定了的话）
     </p>
    </li>
    <li class="listitem">
     <p class="para">
      <em class="emphasis">仅仅</em>在 PHP 5.4.0 之前：
      <var class="varname"><var class="varname">TZ</var></var> 环境变量（如果非空）
     </p>
    </li>
    <li class="listitem">
     <p class="para">
      <a href="datetime.configuration.html#ini.date.timezone" class="link">date.timezone</a> 配置选项（如果设定了的话）
     </p>
    </li>
    <li class="listitem">
     <p class="para">
       <em class="emphasis">仅仅</em>在 PHP 5.4.0 之前： 查询操作系统主机 (如果操作系统支持并允许)。
      This uses an algorithm
      that has to <em class="emphasis">guess</em> the timezone. This is by no means going to work correctly for 
      every situation. A warning is shown when this stage is reached. Do not rely on it to be guessed
      correctly, and set <a href="datetime.configuration.html#ini.date.timezone" class="link">date.timezone</a> to the correct timezone
      instead.
     </p>
    </li>
    <li class="listitem">
     <p class="para">
      如果以上选择都不成功，<span class="methodname"><strong>date_default_timezone_get()</strong></span> 会则返回 <em>UTC</em> 的默认时区。
     </p>
    </li>
   </ul>
  </p>
 </div>


 <div class="refsect1 returnvalues" id="refsect1-function.date-default-timezone-get-returnvalues">
  <h3 class="title">返回值</h3>
  <p class="para">
   返回一个 <span class="type"><a href="language.types.string.html" class="type string">string</a></span>。
  </p>
 </div>


 <div class="refsect1 changelog" id="refsect1-function.date-default-timezone-get-changelog">
  <h3 class="title">更新日志</h3>
  <p class="para">
   <table class="doctable informaltable">
    
     <thead>
      <tr>
       <th>版本</th>
       <th>说明</th>
      </tr>

     </thead>

     <tbody class="tbody">
      <tr>
       <td>5.4.0</td>
       <td>
        不再使用 <em>TZ</em> 来推测时区。
       </td>
      </tr>

      <tr>
       <td>5.4.0</td>
       <td>
        不再根据操作系统的信息来推测时区，因为这是不可靠的。
       </td>
      </tr>

     </tbody>
    
   </table>

  </p>
 </div>


 <div class="refsect1 examples" id="refsect1-function.date-default-timezone-get-examples">
  <h3 class="title">范例</h3>
  <p class="para">
   <div class="example" id="example-2701">
    <p><strong>Example #1 获取默认时区</strong></p>
    <div class="example-contents">
<div class="phpcode"><pre><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br />date_default_timezone_set</span><span style="color: #007700">(</span><span style="color: #DD0000">'Europe/London'</span><span style="color: #007700">);<br /><br />if&nbsp;(</span><span style="color: #0000BB">date_default_timezone_get</span><span style="color: #007700">())&nbsp;{<br />&nbsp;&nbsp;&nbsp;&nbsp;echo&nbsp;</span><span style="color: #DD0000">'date_default_timezone_set:&nbsp;'&nbsp;</span><span style="color: #007700">.&nbsp;</span><span style="color: #0000BB">date_default_timezone_get</span><span style="color: #007700">()&nbsp;.&nbsp;</span><span style="color: #DD0000">'&lt;br&nbsp;/&gt;'</span><span style="color: #007700">;<br />}<br /><br />if&nbsp;(</span><span style="color: #0000BB">ini_get</span><span style="color: #007700">(</span><span style="color: #DD0000">'date.timezone'</span><span style="color: #007700">))&nbsp;{<br />&nbsp;&nbsp;&nbsp;&nbsp;echo&nbsp;</span><span style="color: #DD0000">'date.timezone:&nbsp;'&nbsp;</span><span style="color: #007700">.&nbsp;</span><span style="color: #0000BB">ini_get</span><span style="color: #007700">(</span><span style="color: #DD0000">'date.timezone'</span><span style="color: #007700">);<br />}<br /><br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</pre></div>
    </div>

    <div class="example-contents"><p>以上例程的输出类似于：</p></div>
    <div class="example-contents screen">
<div class="cdata"><pre>
date_default_timezone_set: Europe/London
date.timezone: Europe/London
</pre></div>
    </div>
   </div>
  </p>
  <p class="para">
   <div class="example" id="example-2702">
    <p><strong>Example #2 获取一个时区的简写</strong></p>
    <div class="example-contents">
<div class="phpcode"><pre><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br />date_default_timezone_set</span><span style="color: #007700">(</span><span style="color: #DD0000">'America/Los_Angeles'</span><span style="color: #007700">);<br />echo&nbsp;</span><span style="color: #0000BB">date_default_timezone_get</span><span style="color: #007700">()&nbsp;.&nbsp;</span><span style="color: #DD0000">'&nbsp;=&gt;&nbsp;'&nbsp;</span><span style="color: #007700">.&nbsp;</span><span style="color: #0000BB">date</span><span style="color: #007700">(</span><span style="color: #DD0000">'e'</span><span style="color: #007700">)&nbsp;.&nbsp;</span><span style="color: #DD0000">'&nbsp;=&gt;&nbsp;'&nbsp;</span><span style="color: #007700">.&nbsp;</span><span style="color: #0000BB">date</span><span style="color: #007700">(</span><span style="color: #DD0000">'T'</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</pre></div>
    </div>

    <div class="example-contents"><p>以上例程会输出：</p></div>
    <div class="example-contents screen">
<div class="cdata"><pre>
America/Los_Angeles =&gt; America/Los_Angeles =&gt; PST
</pre></div>
    </div>
   </div>
  </p>
 </div>


 <div class="refsect1 seealso" id="refsect1-function.date-default-timezone-get-seealso">
  <h3 class="title">参见</h3>
  <p class="para">
   <ul class="simplelist">
    <li class="member"><span class="function"><a href="date_default_timezone_set.html" class="function" rel="rdfs-seeAlso">date_default_timezone_set()</a> - 设定用于一个脚本中所有日期时间函数的默认时区</span></li>
        <li class="member"><a href="timezones.html" class="xref">所支持的时区列表</a></li>
   </ul>
  </p>
 </div>

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